The present invention relates to a conductive film, a display device and a touch panel each comprising the conductive film, and a conductive film pattern determination method.
Examples of a conductive film installed on a display unit of a display device (hereinafter, also referred to as a display) include a conductive film for electromagnetic wave-shielding and a conductive film for a touch panel (for example, see JP 2009-117683 A, JP 2002-351341 A and JP 2000-206529 A).
JP 2009-117683 A filed by the applicant of the present application discloses that a second pattern, which is generated from second pattern data in which the relative distance between spectrum peaks of two-dimensional Fourier spectrums (2DFFT Sp) of the pattern data of a first pattern such as a pixel array pattern (for example, a black matrix (hereinafter, also referred to as BM) pattern) of a display and the pattern data of the second pattern such as an electromagnetic wave-shielding pattern is greater than a predetermined spatial frequency, for example, 8 cm−1, is automatically selected.
JP 2009-117683 A also discloses that when the relative distance is not greater than the predetermined spatial frequency, changing of one or more of a rotation angle, a pitch, and a pattern width of the second pattern data to generate new second pattern data is repeated until the relative distance is greater than the predetermined spatial frequency.
In this way, in JP 2009-117683 A, it is possible to automatically select an electromagnetic wave-shielding pattern that can suppress the occurrence of moire and that can avoid an increase in surface resistivity or degradation in transparency.
JP 2009-117683 A and JP 2002-351341 A disclose a liquid crystal display device including a transparent electrode layer or a touch panel having a wiring pattern, a display portion or a display panel having a pixel array pattern, and a lighting device (backlight or front light) having a light guide plate that includes either a prism sheet having a microprism array pattern (hereinafter, also simply referred to as a “prism pattern”) or a prism surface having the prism sheet, in which moire occurring due to interference and the pixel array pattern and the prism pattern can be reduced.
Particularly, JP 2002-351341 A discloses a reflection type liquid crystal display device in which the ridge of the prism surface of the light guide plate of a light guide body of the lighting device is inclined with respect to the repeating pixel arrays of the display panel, such that the occurrence of moire caused by interference between the pixel array pattern and the prism pattern of the prism surface can be inhibited.
Furthermore, JP 2000-206529 A 3 discloses a liquid crystal display device in which a pitch P2 of grooves of the light guide body or an optical sheet such as the prism sheet or a row-like pattern of the microprism of the back light and a pitch P1 of the pixel array pattern of the display panel are set so as to satisfy a predetermined relational expression, or, the relationship between P1 and P2 is specified within a predetermined range, such that the occurrence of moire fringes caused by interference between the pixel array pattern and the prism pattern of the prism surface can be reduced.
Meanwhile, JP 3007008 B discloses an image display-input apparatus for performing both the input of an image (readout of an image source) and the display of an image, which includes an image display-input panel having pixels arrayed patternwise and a backlight having a prism sheet.
JP 3007008 B discloses that by making a pitch of the microprism of the prism sheet of the backlight smaller than a pitch of the pixel array pattern of the display panel, the occurrence of moire caused by interference between the pixel array pattern and the pattern of the prism surface is prevented.